Night-time/daytime Protein S100B serum levels in paranoid schizophrenic patients

Introduction S100B is a calcium-binding astrocyte-specific cytokine, that is considered a biomarker of neurodegeneration; which may be involved in the imbalance of the inflammatory response observed in several brain disorders, including major depression and schizophrenia. Two meta-analyses have reported higher serum levels of S100B in patients with schizophrenia respect to healthy controls. Different studies have described circadian and seasonal variations of biological variables, such as melatonin or cortisol. It has been reported that there is not circadian rhythm of S100B blood levels in healthy subjects. However, it is not known whether there are circadian oscillations in S100B blood concentrations in patients with schizophrenia. Objectives The aim of this study is to describe S100B serum levels in patients with schizophrenia and to analyse whether they follow a circadian rhythm. Methods Our sample consists in 47 patients in acute phase and stabilized status. Blood samples were collected at 12:00 and 00:00 hours by venipuncture. Serum levels of Protein S100B were measured three times: at admission, discharge and three months after discharge. Protein S100B was measured by means of ELISA (Enzyme-linked immunosorbent assay) techniques. Results 12:00 24:00 P ADMISSION 132,95±199,27 85,85±121,44 0,004 DISCHARGE 73,65±71,744 75,80±123,628 0,070 CONTROL 43,49±34,60 40,14±23,08 0,47 P global P Admission Vs. Discharge P Admission Vs. Control P Discharge Vs. Control 0,97 There is a significance difference between 12:00 and 24:00 at admission for the Protein S100B.However, these difference did not occur at discharge and at three months after discharge.It can be interpreted as there is a circadian rhythm of Protein S100B when the patient has got a psychotic outbreak and disappears at discharge and when is psychopathologically stable. Conclusions With respect to our results we can hypothesize that schizophrenic patients in acute relapse present circadian S100B rhythm that is not present when the patients are clinically stable.Furthermore, the decrease of serum protein S100B levels at discharge is indicative of a reduction of the cerebral inflammation, thus it can be a biomarker of cerebral inflammation and this reduction can be the effect of the treatment. Finally, its circadianity could be a guide of this process and clinical improvement. Disclosure of Interest None Declared

Introduction: Schizophrenia spectrum disorders (SSD) are frequently associated with disturbances in both neurocognition and social cognition. The patoetiology of SSD derives from a complex interaction between genes and environment. Exposome score for schizophrenia (ES-SCZ) is a cumulative environmental exposure score for schizophrenia which have shown potential utility in risk stratification and outcome prediction. Objectives: To investigate whether ES-SCZ is associated with cognition in patients with SSD, unaffected siblings, and healthy controls. Methods: The present cross-sectional study included 1141 patients with SSD, 1332 unaffected siblings, and 1495 healthy controls, recruited in the Netherlands, Spain, Serbia, and Turkey. The Wechsler Adult Intelligence Scale (WAIS) was used to evaluate neurocognition, while the Degraded Facial Emotion Recognition (DFAR) task was used to assess social cognition. ES-SCZ was calculated based on our previously validated method. Associations between ES-SCZ and cognitive domains were analyzed by applying regression models in each group (patients, siblings, and controls), adjusted by age, sex, and country. Results: According to our preliminary analyses, no significant associations were found between ES-SCZ and cognition in patients with SSD. ES-SCZ was negatively associated with WAIS in unaffected siblings (B=À0.40, p=0.03) and controls (B=-0.63, p=0.004) and positively associated with DFAR in siblings (B=0.83, p=0.004). No significant association between ES-SCZ and DFAR was found in healthy controls. Conclusions: Our findings show that neurocognition and social cognition are oppositely associated with ES-SCZ. Longitudinal studies may clarify whether there is a cause-effect relationship between ES-SCZ and cognition. Further research should investigate whether ES-SCZ interacts with molecular genetic risk for schizophrenia to improve clinical chcracterization and outcome prediction in people with SSD.

EPP0662
Night-time/daytime Protein S100B serum levels in paranoid schizophrenic patients E. Diaz-Mesa 1,2 , A. Morera-Fumero 2 , L. Torres-Tejera 1 *, A. Crisostomo-Siverio 1 , P. Abreu-Gonzalez 3 , R. Zuñiga-Costa 1 , S. Yelmo-Cruz 1 , R. Cejas-Mendez 1,2 , C. Rodriguez-Jimenez 4 , L. Fernandez-Lopez 2 and M. Henry-Benitez 2 Introduction: S100B is a calcium-binding astrocyte-specific cytokine, that is considered a biomarker of neurodegeneration; which may be involved in the imbalance of the inflammatory response observed in several brain disorders, including major depression and schizophrenia. Two meta-analyses have reported higher serum levels of S100B in patients with schizophrenia respect to healthy controls. Different studies have described circadian and seasonal variations of biological variables, such as melatonin or cortisol. It has been reported that there is not circadian rhythm of S100B blood levels in healthy subjects. However, it is not known whether there are circadian oscillations in S100B blood concentrations in patients with schizophrenia. Objectives: The aim of this study is to describe S100B serum levels in patients with schizophrenia and to analyse whether they follow a circadian rhythm. Methods: Our sample consists in 47 patients in acute phase and stabilized status. Blood samples were collected at 12:00 and 00:00 hours by venipuncture. Serum levels of Protein S100B were measured three times: at admission, discharge and three months after discharge. Protein S100B was measured by means of ELISA (Enzyme-linked immunosorbent assay) techniques.

Results:
There is a significance difference between 12:00 and 24:00 at admission for the Protein S100B.However, these difference did not occur at discharge and at three months after discharge.It can be interpreted as there is a circadian rhythm of Protein S100B when the patient has got a psychotic outbreak and disappears at discharge and when is psychopathologically stable. Conclusions: With respect to our results we can hypothesize that schizophrenic patients in acute relapse present circadian S100B rhythm that is not present when the patients are clinically stable. Furthermore, the decrease of serum protein S100B levels at discharge is indicative of a reduction of the cerebral inflammation, thus it can be a biomarker of cerebral inflammation and this reduction can be the effect of the treatment. Finally, its circadianity could be a guide of this process and clinical improvement.

EPP0663
Analysis of the predictive potential of good clinical response of plasma levels of clozapine in patients with resistant schizophrenia in an area of southern Spain L. I. Muñoz-Manchado 1 *, F. González-Saiz 1 , J. I. Pérez-Revuelta 1 , N. Laherrán-Cantera 1 and R. J. Pardo-Velasco 2 Introduction: Resistant schizophrenia is a schizophrenia subtype characterized by a non-ability to respond to an appropriate antipsychotic treatment in dosage and duration by the patients. These patients show a lower prognostic and symptomatology. The unique drug which has shown efficacy for resistant schizophrenia treatment is clozapine, which is effective in suicide and aggressive behaviour prevention too. Whereas clozapine has numerous and serious adverse effects such as agranulocytosis risk. Because of this, and for guaranteeing an accurate diagnosis of resistant schizophrenia, distinguishing this from pseudo-resistance due to a poor tracing of schizophrenia, clozapine's plasmatic levels monitoring is recommended in Spain by many clinical practise-guidelines.
Objectives: This studio has the objective of determining if altered clozapine's plasmatic levels have predictive potential of therapeutical response and answering what clinical and sociodemographic variables are associated to these anormal plasmatic levels. Methods: In this work, a cross-sectional observational study was carried out in which clinical and sociodemographic data obtained by the Mental Health Unit of the Jerez de la Frontera University Hospital were collected within the research project entitled: "Role of social cognition as a factor psychosocial functioning of the schizophrenic patient" (ECOFUN), of all the participating patients (in total the sample was 141 patients, of which 40 are in treatment with clozapine). Results: The sample of patients has a mean age of 44 years and medium-high educational levels. The vast majority are men and do not currently consume substances of abuse, and when this consumption occurs, tobacco and alcohol are the most consumed substances. Their total scores on the PANSS and Markova Barrios scales are generally very disparate, but with average values of 55 and 16. It has been obtained as results that there is no significant statistical correlation between the plasma levels of clozapine and the values of the PANSS scale and its subscales in the patients. On the other hand, patients treated with clozapine would present clinical and sociodemographic characteristics practically identical to those of patients treated with other antipsychotics, especially their values on the PANSS scale. In addition, plasma levels of clozapine are correlated, although not significantly, with an improvement in the positive symptomatology of schizophrenia. Conclusions: As a conclusion, unusually higher values of clozapine are correlated significantly with lower values in positive symptomatology in schizophrenia, but plasmatic levels are not correlated significantly with values of PANSS scale.

EPP0664
Disorganization in first episode schizophrenia: psychopathological findings and treatment response from a 2-year Italian follow-up research in a real-world setting Introduction: Disorganization is a core dimension of schizophrenia, yet it is relatively under-investigated compared to positive and negative ones, especially at the illness onset. Indeed, most of the empirical studies investigating the disorganized domain included patients with prolonged schizophrenia. Objectives: Thus, the aims of this research were (1) to monitor the longitudinal stability of disorganized symptoms in young patients with First Episode Schizophrenia (FES) along a 2-year follow-up period, and (2) to examine any significant association of disorganization with functioning, psychopathology and the specific treatment components of an "Early Intervention in Psychosis" (EIP) program across the 2 years of follow-up.